Susceptibility to ovarian endometriosis in Polish population is not associated with HLA-DRB1 alleles

BACKGROUND: Endometriosis is associated with inflammatory autoimmune reactions; however, aetiopathogenesis of the disease is still poorly understood. While autoimmune disorders are often associated with particular HLA alleles, the possible involvement of HLA in the aetiopathogenesis of endometriosis is still a subject of controversy. The aim of the study was to examine the distribution of HLA-DRB1 alleles in women with endometriosis. To ensure homogeneity of the studied group, only women with ovarian endometrial cysts were included. METHODS: The study included 65 Polish patients of Caucasian origin in whom ovarian endometriosis had been confirmed by laparoscopic and histopathological examinations. HLA-DRB1 alleles were typed using a reverse slot blot method. A frequency of particular HLA-DRB1 alleles in patients was compared with that of a control group of 700 unrelated ethnically matched individuals as well as 193 age-matched women without endometriosis. RESULTS: No statistically significant differences were found in the distribution of HLA-DRB1 alleles in patients with ovarian endometriosis as compared with control populations. CONCLUSIONS: The results of the present study show that ovarian endometriosis is not associated with particular HLA-DRB1 allele(s). This may suggest that aetiology of this form of endometriosis may be not primarily associated with class II HLA-mediated autoimmune reactions.